VOLVO
ECM-500A - Air conditioning (A/C) line pressure sensor
System
Engine Control Module (ECM)
Volvo models this fault code applies to
This fault code has different meanings depending on model, model year or engine. Select the meaning that applies to your car.
Applies to the following models:
5 modelsS60 (2001–2009), S80 (1999–2006), V70 (2000–2008), V70 XC / XC70 (2001–2007), XC90 (2003–)
Show models by year and engine (10)
- Volvo S60 (2001–2009)2001Engine D5244T only
- Volvo S60 (2001–2009)2002–2003, 2006Engine D5244T, D5244T2 only
- Volvo S60 (2001–2009)2004–2005Engine D5244T, D5244T2, D5244T3 only
- Volvo S80 (1999–2006)2001Engine D5244T only
- Volvo S80 (1999–2006)2002–2006Engine D5244T, D5244T2 only
- Volvo V70 (2000–2008)2001Engine D5244T only
- Volvo V70 (2000–2008)2002–2003, 2006Engine D5244T, D5244T2 only
- Volvo V70 (2000–2008)2004–2005Engine D5244T, D5244T2, D5244T3 only
- Volvo V70 XC / XC70 (2001–2007)2003–2006Engine D5244T only
- Volvo XC90 (2003–)2003–2006Engine D5244T only
What does this fault code mean?
The linear pressure sensor in the A/C system measures the pressure in the refrigerant circuit, and the engine control module reviews the signal. The code can be caused by poor contact or a short in the sensor wiring, but also by too little refrigerant in the system.
Possible causes
- Contact resistance in the connections to the sensor
- Signal wire shorted to supply voltage
- Break in the ground wire
- Damaged A/C pressure sensor
- Low refrigerant charge
- Supply wire to the sensor shorted to supply voltage or ground
What you can do
- 1Read off the fault code, erase it and test-drive to see whether it returns
- 2Make sure the connectors at the sensor and at the engine control module are firmly seated and clean
- 3Have a workshop check the amount of refrigerant, since this needs special equipment
- 4With a multimeter you can look for a break in the ground wire to the sensor
- 5If the fault remains, have a workshop measure the sensor and its wiring
Symptoms you may notice1
- No cold air from the A/C system
General guidance for car owners. Diagnosis on the car can point to a different cause.